The IRA may already have carried out a major new act of disarmament in order to restore Northern Ireland's power-sharing government, Ulster Unionist rebel Mr Jeffrey Donaldson said today.
Mr Donaldson said: "I would not be surprised if the IRA has engaged in an act of decommissioning as a down payment with the [British] government.
"They want elections before Christmas and clearly the Prime Minister needs something to cover himself."
Negotiations to restore the collapsed Stormont administration broke-down earlier this year amid bitter recriminations on all sides.
But with Assembly polls pencilled in for November 13th, London and Dublin have been involved in a frantic drive to break the deadlock.
Mr Blair held talks with Sinn Féin leaders Mr Gerry Adams and Mr Martin McGuinness at Downing Street today.
More discussions between Mr Adams and Mr David Trimble are due to be held in Belfast tomorrow with elections expected to be announced next week.
Republicans have been demanding guarantees that the UUP will no longer be able to bring down the devolved institutions which fell 12 months ago amid claims of an IRA spy operation.
But unionists insist they will not go back into government with Sinn Féin until they receive cast-iron assurances the IRA will be wound up.
It is believed Mr Trimble has privately speculated that the IRA may already have put more weapons beyond use. The claims were dismissed, however, by Sinn Fein sources close to the negotiations.
"This is nonsense and rubbish," said one.
A spokesman for Gen de Chastelain, who is understood to be in Northern Ireland, also played down the claims.
He said: "I cannot tell you of any report that we would have put to the Governments. I have no knowledge of that." Mr Donaldson claimed whatever the Provisionals do has to be more concrete this time.
"We need to see a proper process dealing conclusively not only with weapons decommissioning but also paramilitary activity.
"Proper and visible verification must take place; a mere report of secret decommissioning the last time did not build confidence.
"Any repetition of that kind of farce really will not cut the mustard."
PA